CAMBRIDGE, Mass.--(BUSINESS WIRE)--Genzyme,
a Sanofi company (EURONEXT: SAN and NYSE: SNY), today announced positive
new data from the Phase 3 ENGAGE and ENCORE studies of eliglustat
tartrate, its investigational oral therapy for Gaucher disease type 1.
The results from the ENGAGE study were presented today at the 9th
Annual Lysosomal Disease Network WORLD Symposium in Orlando, Fla. In
conjunction with this meeting, Genzyme also released topline data from
its second Phase 3 study, ENCORE. Both studies met their primary
efficacy endpoints and together will form the basis of Genzyme’s
registration package for eliglustat tartrate.

The company is developing eliglustat tartrate, a capsule taken orally,
to provide a convenient treatment alternative for patients with Gaucher
disease type 1 and to provide a broader range of treatment options for
patients and physicians. Genzyme’s clinical development program for
eliglustat tartrate represents the largest clinical program ever focused
on Gaucher disease type 1 with approximately 400 patients treated in 30
countries.

“The data presented at this year’s WORLD symposium reinforce our
confidence that eliglustat tartrate may become an important oral option
for patients with Gaucher disease,” said Genzyme’s Head of Rare
Diseases, Rogerio Vivaldi MD. “We are excited about this therapy’s
potential and are making excellent progress in our robust development
plan for bringing eliglustat tartrate to the market.”

ENGAGE Study Results:

In ENGAGE, a Phase 3 trial to evaluate the safety and efficacy of
eliglustat tartrate in 40 treatment-naïve patients with Gaucher disease
type 1, improvements were observed across all primary and secondary
efficacy endpoints over the 9-month study period. Results were reported
today at the WORLD Symposium by Pramod Mistry, MD, PhD, FRCP, Professor
of Pediatrics & Internal Medicine at Yale University School of Medicine,
and an investigator in the trial.

The randomized, double-blind, placebo-controlled study had a primary
efficacy endpoint of improvement in spleen size in patients treated with
eliglustat tartrate. Patients were stratified at baseline by spleen
volume. In the study, a statistically significant improvement in spleen
size was observed at nine months in patients treated with eliglustat
tartrate compared with placebo. Spleen volume in patients treated with
eliglustat tartrate decreased from baseline by a mean of 28 percent
compared with a mean increase of two percent in placebo patients, for an
absolute difference of 30 percent (p<0.0001).

Secondary endpoints also improved:

Platelet levels increased from baseline by an absolute difference of
41 percent compared with placebo (P<0.0001)

Hemoglobin levels increased from baseline by an absolute difference of
1.2 g/dL compared with placebo (P<0.0006)

Liver volume decreased from baseline by an absolute difference of
seven percent compared with placebo (P<0.0072)

Among tertiary endpoints:

A statistically significant improvement in total bone marrow burden
was observed among patients in the eliglustat tartrate arm compared to
placebo, and all other markers of bone disease showed trends towards
improvement.

In the study, there were no serious adverse events reported in either
treatment group. All adverse events reported were mild or moderate, with
the most common being headache, arthralgia and diarrhea. One patient
withdrew from the trial, for a reason not treatment-related. At the end
of the nine months, patients who were on placebo were transitioned to
eliglustat tartrate.

ENCORE Study Results:

ENCORE, the second Phase 3 trial in the eliglustat tartrate development
program, also met its primary efficacy endpoint.

ENCORE is a multi-national, randomized, controlled, open-label, study
designed to determine whether eliglustat tartrate is non-inferior to
Cerezyme® (imiglucerase for injection). In the trial, 160
patients with Gaucher disease type 1 who had begun enzyme replacement
therapy at least three years prior to randomization and who had reached
therapeutic goals were randomized (2:1) to receive either eliglustat
tartrate or Cerezyme for one year.

The primary efficacy endpoint of stability was a composite endpoint of
pre-specified change criteria for each of the following parameters:
spleen volume, hemoglobin levels, platelet counts, and liver volume. To
meet the endpoint for stability, a patient had to remain stable in all
four parameters. Eliglustat tartrate met the pre-specified criteria for
non-inferiority to Cerezyme, with the majority of patients in both
groups remaining stable one year after randomization (84 percent of
eliglustat tartrate patients and 94 percent of Cerezyme patients).

In an additional, pre-specified, efficacy analysis of the percent change
in spleen volume from baseline, a mean change of minus six percent was
observed in the eliglustat tartrate arm compared with minus three
percent in the Cerezyme arm. This analysis also met the criteria for
non-inferiority.

With regard to secondary endpoints, after one year, nearly all patients
receiving eliglustat tartrate met the stability criteria for the
individual components of the composite endpoint:

94 percent of patients met spleen volume criteria

95 percent of patients met hemoglobin levels criteria

93 percent of patients met platelet levels criteria

96 percent of patients met liver volume criteria

The majority of patients had normal bone mineral density scores at study
entry for total femur and lumbar spine. These scores were maintained
over the 12-month study period.

In the ENCORE trial, two percent (n=2) of eliglustat tartrate patients
and two percent (n=1) of Cerezyme patients discontinued treatment
because of an adverse event. Over the course of one year, four adverse
events were observed in the eliglustat tartrate treatment group with ≥10
percent incidence compared with Cerezyme: fatigue (14 percent overall
incidence), headache (13 percent overall incidence), nausea (12 percent
overall incidence), and upper abdominal pain (10 percent overall
incidence). The majority of adverse events (AEs) were mild or moderate
in severity for both groups. There were no serious adverse events in the
study that were considered to be related to therapy by the treating
physician.

The results from the ENCORE study are expected to be presented at a
medical meeting in the second half of the year.

About Gaucher disease

Gaucher disease is an inherited condition affecting fewer than 10,000
people worldwide. People with Gaucher disease do not have enough of an
enzyme, β-glucosidase (glucocerebrosidase) that breaks down a certain
type of fat molecule. As a result, lipid engorged cells (called Gaucher
cells) amass in different parts of the body, primarily the spleen, liver
and bone marrow. Accumulation of Gaucher cells may cause spleen and
liver enlargement, anemia, excessive bleeding and bruising, bone disease
and a number of other signs and symptoms. The most common form of
Gaucher disease, type 1, generally does not affect the brain.

About eliglustat tartrate

Eliglustat tartrate, a novel glucosylceramide analog given orally, was
designed to partially inhibit the enzyme glucosylceramide synthase,
which results in reduced production of glucosylceramide.
Glucosylceramide is the substance that builds up in the cells and
tissues of people with Gaucher disease. The concept was initially
developed by the late Norman Radin, MD, from the University of Michigan.
In pre-clinical studies, the molecule, developed with James A. Shayman,
MD, also from the University of Michigan, has shown high potency and
specificity. Initiation of the Phase 2 and 3 studies of eliglustat
tartrate in Gaucher disease followed an extensive pre-clinical research
effort and a Phase 1 program.

Cerezyme Important Safety Information

Cerezyme (imiglucerase for injection) is indicated for long-term enzyme
replacement therapy for pediatric and adult patients with a confirmed
diagnosis of Type 1 Gaucher disease that results in one or more of the
following conditions: anemia (low red blood cell count),
thrombocytopenia (low blood platelet count), bone disease or
hepatomegaly or splenomegaly (enlarged liver or spleen).

Approximately 15% of patients have developed immune responses
(antibodies). These patients have a higher risk of an allergic reaction
(hypersensitivity). Use Cerezyme® (imiglucerase for injection) carefully
if you have had an allergic reaction to the product in the past.
Symptoms suggestive of allergic reaction happened in 6.6% of patients,
and include anaphylactoid reaction (a serious allergic reaction),
itching, flushing, hives, an accumulation of fluid under the skin, chest
discomfort, shortness of breath, coughing, cyanosis (a bluish
discoloration of the skin due to diminished oxygen), and low blood
pressure.

Side effects related to Cerezyme administration have been reported in
less than 15% of patients. Each of the following events occurred in less
than 2% of the total patient population. Reported side effects include
nausea, abdominal pain, vomiting, diarrhea, rash, fatigue, headache,
fever, dizziness, chills, backache, and rapid heart rate. Because
Cerezyme therapy is administered by intravenous infusion, reactions at
the site of injection may occur: discomfort, itching, burning, swelling
or uninfected abscess. Cerezyme is available by prescription only. For
full prescribing information, please visit www.genzyme.com.

About Genzyme, a Sanofi Company

Genzyme has pioneered the development and delivery of transformative
therapies for patients affected by rare and debilitating diseases for
over 30 years. We accomplish our goals through world-class research and
with the compassion and commitment of our employees. With a focus on
rare diseases and multiple sclerosis, we are dedicated to making a
positive impact on the lives of the patients and families we serve. That
goal guides and inspires us every day. Genzyme’s portfolio of
transformative therapies, which are marketed in countries around the
world, represents groundbreaking and life-saving advances in medicine.
As a Sanofi company, Genzyme benefits from the reach and resources of
one of the world’s largest pharmaceutical companies, with a shared
commitment to improving the lives of patients. Learn more at www.genzyme.com.

About Sanofi

Sanofi, a global and diversified healthcare leader, discovers, develops
and distributes therapeutic solutions focused on patients’ needs. Sanofi
has core strengths in the field of healthcare with seven growth
platforms: diabetes solutions, human vaccines, innovative drugs,
consumer healthcare, emerging markets, animal health and the new
Genzyme. Sanofi is listed in Paris (EURONEXT: SAN) and in New York
(NYSE: SNY).

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